do the doors rattle??
if so try and alter the shoot bolt reciever at the top and bottom of the
slave door.
also check the doors for level and plumb there must be no bows in the frame.
if its fitted straight and the doors shut ok without catching,there are round
catches with an allen key ajustment if you turn are oval and increase
tension on the catches,
There should also be ajustments on the hinges to move the door a few
milimetres over to the slave door,spray wd40 on all catches and hinges
before turning.
If you want to replace the seals only cut a small section from the door
rebate and take it to any conservatory company they usually have spare
rolls of it.
Unfortunatly if the doors are not level or plumb the frame needs to be refitted.
hope this helps